Double-storey extensions for homes in Burnham-on-Sea
From the first sketch to final sign-off, we plan and build double-storey extensions in Burnham-on-Sea and the surrounding Somerset area.
- Guide price in Burnham-on-SeaFrom £38,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsTA8, TA9
Do I need planning permission in Burnham-on-Sea?
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
What is included
- Breaking through at both levels, stairs and landing changes where needed
- Ground and first floor structure, roof tied into the existing roof
- Foundations sized for two floors
- Insulation, plastering, electrics and plumbing to finish
- Measured survey, design and planning drawings
- Householder planning application where needed
Working in Burnham-on-Sea
We cover Burnham-on-Sea and the postcode districts TA8, TA9. We also work in nearby Weston-super-Mare (7 miles), Bridgwater (8 miles), Clevedon (15 miles), Taunton (16 miles).
South West homes range from terraced streets in the cities to stone cottages and bungalows in the countryside, and conservation areas are common in historic centres.
Guide prices for Burnham-on-Sea
These guide figures apply our South West England adjustment (×1.02) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Burnham-on-Sea: £1,580 to £3,060 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £38,500 – £46,500 | £44,000 – £58,000 | £56,000 – £73,500 |
| 4 m × 4 m, two floors 32 m² | £50,500 – £60,500 | £58,500 – £77,000 | £75,000 – £98,000 |
| 4 m × 6 m, two floors 48 m² | £75,500 – £91,000 | £88,000 – £115,500 | £112,500 – £147,000 |
For a figure based on your own dimensions, use our guide-price tool.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Double-storey extension questions answered
Do I need building regulations approval in Burnham-on-Sea?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Burnham-on-Sea, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do you cover all of Burnham-on-Sea?
Yes. We cover Burnham-on-Sea and the surrounding parts of Somerset. Site visits are free and there is no obligation.
Does a double-storey extension need planning permission?
Often, yes. In England a two-storey rear extension can be permitted development only if it projects no more than 3 m and sits at least 7 m from the rear boundary, with matching roof pitch and obscure side windows. Side extensions over one storey always need planning permission. We confirm the route at the survey.
Do I need a Party Wall Agreement?
If you are in England or Wales and the work involves a shared wall or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We tell you which notices are needed.
Book a free site visit in Burnham-on-Sea
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.